However, overall, Mari did enough to impress manager Steve Bould, who said the two central defenders provided plenty of guidance to the young Gunners.

"It’s fabulous for the young players to play alongside them," Bould said. "It’s a learning programme and we don’t very often get older boys and men playing with us, and that’s how I learned my game when I was a kid so it’s something we miss out on lots of times.

"It was actually a very good game for them to come in to. I think Chelsea’s striker is a good player and they have good players all over the park so it was a good test for them and a good 45 minutes. I’m sure they will go on and use that for first-team value."

He added: I thought the performance was really really good, especially in the second half. I think they edged the first half they had a bit more of the ball and we struggled a little bit to retain it.

"In the second half, the boys have done everything that we’ve asked of them and I couldn’t ask of any more from them apart from scoring another goal."

Forward Trae Coyle, meanwhile, played all 90 minutes after recently recovering from an injury.

And the winger was left impressed by Mari, even if Arsenal couldn't do enough to get the win on the day.

"We’ve played with Rob a lot of times and he’s always been good with us," Coyle said.

"Obviously he has so much ability and I was very impressed with Pablo as well. Playing with those two was definitely a big help today."

"We played well, it’s disappointing because I felt like we had the better chances so it’s a bit disappointing that we didn’t take any points," he added. "We’ll go again next week and hopefully we can put it right."

The Arsenal first team are fresh off a 4-0 battering of Newcastle on Sunday, with Pierre Emerick-Aubameyang, Nicolas Pepe, Mesut Ozil and Alexandre Lacazette providing the goals.

Currently sitting in 10th place, Mikel Arteta's side will face Olympiacos this week in the first leg of their Europa League tie before taking on Everton this weekend in their return to the Premier League.